Power-based training is without a doubt the best way to structure training for cycling. However, if your FTP isn’t accurate you could be missing out on the benefits of training with power.
** Our default testing format to estimate an athlete’s FTP was changed to the TrainerRoad Ramp Test since this post was published
Training with Power Explained
Power-based structured interval training is one of the most accessible and accurate ways to measure performance for cyclists. With a power meter, you’re able to precisely measure how much work is required of your body at any given second of your ride.
The crux of power-based training is a benchmark called FTP, which stands for Functional Threshold Power. This acronym represents a close-enough representation of your lactate threshold in terms of power and is a benchmark used to scale every interval to your specific needs. That way, you can be sure that you’re training at exactly the right intensity at all times.
However, if your FTP is not accurate, then you’re essentially using a ruler that appears normal, but has incorrect inch measurements.
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Try Plan BuilderReasons Your FTP Could be Inaccurate
Your FTP is assessed through a structured test that should push you to exhaustion. If you are training regularly, you should reassess every 4-6 weeks. While training, as more time passes between testing, it’s highly probable you’ve gotten stronger and that your FTP from your previous test is now too low.
Interestingly enough, your effort in a testing interval is a maximal effort, so while testing above your limits during that interval is fundamentally impossible, there are a couple of exceptions. Firstly, if you your last FTP test was taken while you were at your peak, and you’ve since taken time off, that FTP will likely be too high for your current fitness. A more common scenario is one where a rider is doing a workout that contrasts to their current abilities. For example, if a long-distance triathlete is trying to complete a neuromuscular sprint workout, chances are they will feel their FTP is too high. The same would be true for a cyclocross racer trying to complete a 30-minute threshold interval. In this case, their FTP could be accurate, but they are asking their body to work in a way that is completely foreign.
All that being said, it is certainly possible to under-assess your potential. When riders enter a test already fatigued from a previous day’s training, hold back, lose focus or pace incorrectly, they are sure to alter their results.
FTP testing is a skill in itself — every rider experiences a learning curve as they reassess every 4-6 weeks. With that in mind, new riders can safely assume that their FTP from their early assessments may be close, but not spot on. That’s not necessarily a bad thing at first.
Since new riders are exploring their limits and familiarizing themselves with riding at those limits, their “actual FTP” may differ from their “performable FTP”. This decoupling is resolved quickly with increased familiarity to training, and there are a number of signs to look for that indicate your FTP is too low.
Signs of a Low FTP
Rest intervals are too easy
This is the most common problem for cyclists who are new to power-based training. Due to inexperience, their FTP is low and it is noticed in subsequent super-tempo interval workouts. If your workout has you training at or above sweet spot, you should be looking forward to your rest intervals and need to take them easy in order to be ready for the next work interval.
When riders can ride well above the indicated power during a rest interval, they’re either hampering their recovery for the next interval or seeing further evidence that their FTP was underestimated. But in too many cases, the rider goes from working a little too hard during the recovery interval and not hard enough during the work interval.
If this is the case, try bumping the intensity of the workout 2-3% and see if those rest intervals transform from a bore to a godsend.
Over-under intervals aren’t exhausting
These type of interval workouts have you working just below threshold for a period of time before going just above threshold. This pattern repeats any given number of times during each interval set.
Over-unders are known for being very challenging both mentally and physically. The reason for this is because your body is forced to exceed its lactate processing limits and recover just below those limits. Mental and physical triggers cry out for full rest in order to recover, but you are teaching your body to recover while still working hard.
After each “over”, you should feel a burning or flooded sensation in your muscles and be out of breath. If you don’t feel these sensations, it’s a good sign that the “over” portion of your intervals aren’t truly over your threshold. Try increasing the intensity 2-3%.
Long threshold intervals are too easy
Certain workouts will have you riding at threshold for extended periods of time with little rest. For example, Lamarck‘s four threshold intervals are 10 minutes long with only two minutes rest in between. This workout can be a great litmus test for your FTP accuracy.
If you can sustain 40 minutes at FTP with minimal rest and don’t feel thoroughly challenged, at least eager for recovery during the final minute or two of each effort, then chances are your FTP is too low. The same fix of raising your FTP 2-3% is suggested.
How to Make Sure Your FTP Is Accurate
There’s only one sure-fire way to make sure your FTP is accurate, and that is through regular testing. With time, FTP testing will transform from something exciting to something dreadful and then back to something exciting again. If you have any doubts in the accuracy of your FTP, you can apply that quick fix of a 2-3% intensity increase until you feel you’re in the right spot, but I always advocate testing as the best way to resolve this issue.
Listen to Certified Cycling Coaches Discuss FTP Testing
Low FTP is one topic we covered in episode 26 of the Ask a Cycling Coach podcast. Listen to the episode’s full recording below to hear this and other questions from cyclists get answered by our certified cycling coaches.
Additional Notes
TrainerRoad’s Ask a Cycling Coach podcast is dedicated to making you a faster cyclist. It gives you the chance to get answers to your cycling and triathlon training questions from USAC certified coaches Chad Timmerman, Jonathan Lee and special guests. Learn more about other topics we covered in the latest episode with our resources below:
- Do different types of trainers affect your FTP?
- How inertia affects FTP
- How to use cycling to lose weight
- How power relates to VO2max
- What should females know about body fat analysis
- Is it normal to not see an increase in FTP?
- Does expensive cycling kit make you faster?
- Is your FTP too low?
- What is VO2max?
- Does VO2max training make you faster?
- What your body goes through during an interval workout
For more answers to your cycling training questions, listen to our podcast Ask a Cycling Coach — the only podcast dedicated to making you a faster cyclist. New episodes are released weekly.
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I actually submitted a question for this week’s podcast along these lines…
When I did my first 8 minute test a few weeks ago I felt like I pushed myself pretty hard, but perhaps I could have paced myself a bit better. I’ve been doing SSB LV1 along with some endurance rides and have really felt a huge increase in fitness over a short period of time. I’ve been experiencing exactly what you describe above as far as longer sweet spot intervals not feeling terribly challenging and not taking it as easy during rest intervals (although this is largely due to using Trutrainer rollers and needing to maintain a certain speed to stay stable). This has been the case even when bumping things up by 10%. Based on a recent workout (Eclipse) it’s looking like my FTP is probably around 306. This is a ridiculous ~29% increase from the 238 I tested at. My concern is that if I adjust my FTP accordingly there will be a massive jump in intensity quite suddenly. I suppose I just need to listen to my body, but is there any reason why you wouldn’t suggest such a jump if prior workouts have demonstrated I should be able to handle it? (i.e. Would ramping up over the course of a week or two be a better approach?)
Thanks!
You’re on the right track with this one Keith. I’d raise the intensity slowly until you get to that point where you anticipate your FTP may be. Pardon the usage of this saying, but I’m sure it will be painfully obvious where that limit is. 🙂
Right on, thanks dude. I am actually doing all right so far with the straight jump to 306. Feel like this is way closer to where I should be as far as perceived effort during intervals. Power meter arrives tomorrow so will be good to get an idea of where I actually stand wattage-wise.
Good to hear Keith! You will most likely see a difference between your VP and Power meter data, but this is to be expected. Whenever I install a new power meter I disregard the power numbers from my previous PM and start anew. I’ve even seen small yet noticeable disparities between two of the same model.
Congrats on making the jump to a PM!
I’ve been thinking a lot about this since the pod cast. I really hate doing the testing because it hurts so bad and I had been doing the 20 min test. I dislike it enough that I skipped the last one Rx’d for Sweet Spot Base LV1.
After listen to Chad I think I’m going to switch to the 8 min test, get warmed up start the test at my current FTP for say 2 min then just try and smash the last 6 min by steady hard riding! Has anyone else tried this normally for the 20 min I pick a lose target to shoot for take a few minutes to settle in at the current FTP then start increasing as I go.
Thanks for the awesome product I’ve seen huge increases going from FTP of 200 in January to FTP of 246 currently and I’ve lost 12 lbs. from 172 to 160 currently. It has made a big difference that I really felt in the first race of the year. It’s all virtual power no power meter yet but it is clearly working.
Hey Nick,
It definitely sounds like the 8 Minute Test could be a good option for ya. It is for me personally, but many athletes see little to no difference between testing results from both tests.
Regarding your pacing effort, I’d definitely advise against any type of tiered pacing. While starting out conservative is a good choice, I wouldn’t put a specific number on your pacing. Pacing during an FTP test should be based off of perception of effort. The effort is ideally a consistent effort from beginning to end, where any variation in your power profile would appear as a very subtle smile.
I’m just finishing Sweet Spot Base Mid I – starting week 6 today. On a 0-dark-30, out of bed and onto trainer weekday routine. But to avoid under-testing I want to be well rested and fueled for the FTP test scheduled at the start of Sweet Spot II next week. I’m thinking then of shifting the FTP test to this coming weekend, which is supposed to be the last two days of Base I. Leaning toward doing the test on Saturday, after Friday’s rest and in place of Andrews. Then I’ll do the scheduled 2-hours on Sunday and sub in something else next Tuesday. What do you guys think? Is Monday-Friday (with the scheduled rest week rides on Tue. and Thu.) enough rest to test well on Saturday? Safe to apply similar shift as I work through build and specialty plans the rest of season? (I’m 45)
Hey David,
I like your approach of giving yourself a day or two to rest prior to the test. There’s no official rule stating you need X days of rest before an FTP test because each person will respond to work and rest uniquely.
Having said that, I’d think that one day of rest should be sufficient. If you don’t feel fully rested on Saturday, do some easy pedaling and push back to Sunday.
Use this weekend as an experiment to see how your body responds to this format. If it works well, I would definitely advocate utilizing this format in the future.
In my case I always like to have one day off before an FTP test, and then a day of leg openers the next day. Just what I’ve found to work for me after trial and error 🙂
Thanks for advice Jonathan, I took it – here’s a long (sorry) but thorough description of the result.
I’ve heard you guys say that FTP test results, by definition, can’t be too high. And I’ve also heard you say that using the 8-minute test it’s OK to essentially throw away one of the two 8-minute blocks (if it didn’t work out for some reason), and manually set your FTP at .9x the keeper 8-min. So if I’ve done that, can my FTP in fact be too high?
I’m 45, going into 2nd full year racing CX, and while it’s my first full year on TrainerRoad plans I had been following other (albeit lesser) structured plans for a few years and started on yours latter half of last year.
When I tested to begin Sweet Spot Mid I (https://www.trainerroad.com/cycling/rides/3260629-8-minute-test), I did it fasted at 5am (my normal weekday routine), poorly rested and in the midst of a head cold – less than ideal! So after what I thought was a solid and consistent first 8-min. effort, I totally fell apart a few minutes into the second 8. I backed off, chalked it up to poor fueling, rest and health, and manually set my FTP based on the first interval at 231.
Sweet Spot Mid I went well – only missed one workout, did the Sunday endurance rides outside. While the week 4,5 Saturday over-unders were hard – I reduced 3% for one them and back-pedaled a bit during some unders in both – I made it through them.
Per your much appreciated advice to avoid the perceived mistakes with the last FTP test, I moved my test for the start of Sweet Spot Mid II to the weekend. So with adequate rest, health and breakfast on board I tested this past Saturday (https://www.trainerroad.com/cycling/rides/3518001-8-minute-test). I thought I nailed the first block – you can see my watts starting to waver to in last 2 min., but I held on. And it was only a very modest 1% increase from the FTP I’d used the last 6 weeks. As the second block started I had trouble even maintaining that same power and really fell apart a few minutes in. Again I backed off. Felt like it was my heart/lungs stopping me more than my legs (though they hurt too). Again I’ve manually set my FTP from the first block alone, to 234 now.
This morning I did Mount Baldy -2 (https://www.trainerroad.com/cycling/rides/3532483-mount-baldy-2) in place of the scheduled FTP test to start Base II. It was a tough workout, but manageable. No decreases or backpedals and I was only really huffing and puffing for the end of the third block. Figured this would also be a good indicator workout for the accuracy of my FTP.
What do you think? I’m a bit demoralized with FTP testing now, and wondering whether I’m truly making significant fitness gains.
Thanks for the tips. I’ve been using TR for the past few years and have always tended to bump up my FTP 1-2 watts per week to try to keep pace with my fitness improvements from one FTP test to the next. It’s usually works out fairly well in that I often find my next suggested FTP from the test matching closely with where I have my current FTP set. But this last block didn’t follow that pattern. I have just completed SSB level 2 heading into the sustained power build plan. I started the 20 min test with my current FTP at 275. The last few workouts in the SSB plan were challenging but not impossible. But man, the test kicked my butt. I ended up getting a suggested FTP of 265 watts. I was a bit surprised since I didn’t feel that was on track with what I’ve been able to handle recently. I chalked it up to a random day of poor mental toughness. It happens. But is it reasonable to constantly add a few watts each week throughout a block of a plan? And would it also be reasonable to expect more increases per week during the build phase vs. base?
Hey Russ,
Adding a couple of watts each week will work for a certain length of time, but as time progresses and you get closer to your physiological potential, you’ll see a decreased rate of improvement. For that reason, I’d suggest training at whatever FTP your previous assessment delivered, unless that feels far away from your potential.
However, you are spot on in recognizing that different training phases will yield different rates of improvement. It is normal to see substantial increases in FTP toward the end of your Base Phase, and this will continue as you move through the Build Phase. Once you have entered your Specialty Phase you should see a lower rate of improvement in FTP, and in some cases, you won’t see any improvement in FTP. This is due to the intent of the Specialty Phase being refinement rather than growth.
What is your view on what level is “too low” to achieve the desired physiological outcomes? 1%,3%,5%? I ask as I had a failed FTP test (had to break in middle) earlier this week that still generated a modest increase in calculated FTP, but a bit lower where I thought I would end up. I’ve done two workouts since, and the data shows that I’ve been over-powering my intervals by 1-3% with no notable power fade on the last intervals. I’m concerned about going off my gut feel and increasing my FTP so soon after a test, but also worried about not getting the most from the plan. I know these are small percentages – but do they make a difference in training?
On the over-powering – I run virtual power on a fluid trainer – so always difficult to get strong precision over an interval – especially as the power climbs and the intervals become shorter.
Hi, I have a question about recovering from illness. I have been totally off the bike for 3 weeks and it sucks. Anyway I’ve been back on the trainer before hitting the road. I’m still able to hit my FTP but obviously, not able to sustain it as much as before. Should I conduct a new FTP test or keep my current FTP and go to build phase until I could sustain it again?
Hey Jan! Glad you’re back on the bike. It’ll definitely be a good idea to reassess your FTP before getting started to account for any fitness you may have lost in your few weeks off the bike. I’m sure it won’t be much of course. 😉
I tested my FTP with TR’s 20 min test and came up with a score of 68! When I did the 8 min test, I was at 73!
I am a very slow and not strong cyclist (avr. only 12-13mph on the road with a road bike) but even for that felt 73 FTP was way too long. I’m not able to figure out what I am doing wrong.
I tested the FTP on a wahoo kickr and I’ve calibrated it properly.
Max, if its any comfort, I have been using the 8 min test during sweet spot base and into build. However half way through build I hit the wall and had to take 4 days complete rest. I racked my brains trying to figure out what the issue was. I moved to the 20 min test and this showed a reduced FTP of 12 watts from 257 to 245. I think the 20 min is more accurate, and would suggest I was working too hard using the 8 min test FTP, hence the reason I hit the wall.
hi quick question i did both the 20min and 8min test when i started my training. 20min i averaged 243 watts for the 20mins so FTP of about 230 watts yet with the 8min i averaged 270 so an FTP of about 243watts. i used this my first 6 week SSB training and it seemed about right. moving into the Sustained power build plan i did the 20min test as it says and came back with a FTP of 246 watts which feels low. have done the first workout and it felt super easy, it was a tempo work out and my heart rate never moved out of zone 2. What do you suggest? retest using the 8min FTP test or move the FTP up by a few watts?
I’ve just finished my first 8-minute FTP test on TrainerRoad and I am negatively surprised by how low my FTP is. It is 181. I already did an FTP test before (using a different software) that was around 230.
Maybe there is something wrong with my software setting or with my smarttrainer. Can anyone help me? Thanks
Did you do the tests witht the same environment? I.E. same tire lressure, same trainer or same power meter?
Generally if you do a test without a power meter, results are usually high than with a power meter.
Nick,
Shoot us an email at support@trainerroad.com and we’ll be happy to see what’s up. 🙂
We’ll look forward to hearing from you—thanks!
Another good way to make sure that your FTP is accurate is to monitor HR as well during long sweetspot workouts (88%-94% FTP intervals). For me, I found that my AVERAGE heart rate for sweeptspot starts at 77% HRMax (or 88% of Threshold HR) and ends around 85% HRMax (or97% of THR) during these intervals. If your HR is still below/above these limits after two or three intervals, it’s time to reasses or to adjust intensity by 2/3%.
Thanks for your input Aurelien!
I am using a Kinetic smart trainer and confused about what gears I should use for the FTP test. I did my first on the smallest gear (to the pedals) and relatively low secondary gear (apologies in advance, relatively new to cycling so not sure of all the terminology).
What hearing do you suggest is used during the FTP test?
Hey Man!
When in the FTP test phase, you should shift into whatever gear has you spinning at a comfortable and efficient cadence. For most people, this lies between 80 and 100 rpm. Shift your gear around until you are spinning efficiently when working at your physical limit, and this will lead to the best results for your test. When you are not in an FTP test and are simply training in ERG mode, you will have the best results in your easiest possible gear (small chainring, big cog). This results in lower wheel speed, less noise, and faster ERG response 🙂
If you have any more questions, don’t hesitate to reach out to support@trainerroad.com, they’ll always be there to help!